Multi-layer shingle with shiplap joint

ABSTRACT

A multi-layer laminate shingle has a base layer and at least a second layer above the base layer. At one end of the shingle the base layer projects beyond the second layer while at the other end the second layer projects beyond the base layer. When the shingles are laid in a course along the roof, the projecting end of the second layer overlaps the projecting end of the base layer of the next shingle, forming a shiplap joint over all or substantially all of the width of the shingle, protecting the joint against rain penetration. This shiplap feature allows the headlap to exposure ratio of the shingle to be reduced to less than 1 and even to 0.5 or less, thus reducing the cost of shingles per unit of roof coverage area. If desired, a narrow strip can be adhered to the top of the headlap portion of the shingle or beneath the butt portion of the shingle to emulate the appearance of a costly triple laminate shingle.

FIELD OF THE INVENTION

[0001] This invention relates to the designs of multi-layer shingles. Inparticular, it relates to multi-layer shingles having shiplap joints.

BACKGROUND OF THE INVENTION

[0002] Asphalt roofing shingles have been in general use on roofs fornearly 100 years. They provide excellent water shedding characteristicsto protect roofs from water leaks. The shingles are installed on a roofand overlap each other in a way that water cannot-leak through thejoints of the shingles to the base board of the roof. Typically, eachcourse of shingles is horizontally offset, about 4″ to 10″, relative tothe preceding course of shingles so that the joints of the shingles in acourse do not line up with the joints of the shingles in the precedingor succeeding course. In addition, except for the starter course, eachcourse of shingles overlaps the preceding course of shingles by morethan 50% of the shingle width. This is to ensure that all portions ofthe joints in the same course either are placed on top of the shinglesin the preceding course or are covered by shingles in the succeedingcourse. This means that over 50% of the total shingle surface area iscovered by other shingles, which is a costly use of material.

[0003] A shingle surface can be divided into two areas, called the“headlap portion” and the “exposure portion”. After the shingles areinstalled on the roof, the headlap portion is the area of the shinglecovered by the shingles of the succeeding (i.e. next higher) course ofshingles, while the exposure portion is the area of the shingle exposedto the environment. More overlapping area means less roof coverage areafor the shingle. Hence, the higher the ratio of the headlap portion tothe exposure portion, the higher the shingle cost per unit of roofcoverage area is, because a larger overall shingle area is required toprovide an amount of exposure which is equal to the roof coverage area.In order to maintain the water shedding integrity of the shingle system,the headlap to exposure ratio cannot (in the prior art) be reduced toless than one.

BRIEF SUMMARY OF THE INVENTION

[0004] While single layer shingles are very common, due to their lowprice, double layer and triple layer laminate shingles are becoming morewidely used, because of their attractive ornamental appearance. Theapplicant has realized that when such multiple layer laminate shinglesare used, their multiple layer construction can be used to provide ashingle design which can substantially reduce the headlap to exposureratio of the shingle, while maintaining the water shedding integrity ofa roofing system formed from such shingles.

[0005] In one aspect the invention provides a roofing shinglecomprising: (a) a base layer having first and second longitudinallyspaced-apart end edges defining between them a length for said baselayer, said base layer also having laterally spaced-apart top and bottomedges defining a width for said base layer, said base layer having anupper surface, (b) a second layer laminated to said upper surface ofsaid base layer, (c) said second layer having a first end portion insetfrom said first end edge of said base layer over at least a substantialportion of the width of said base layer, said first end portion beinginset from said first end edge from a position adjacent said top edge ofsaid base layer to a position at or near said bottom edge of said baselayer, so that said first end edge of said base layer extends in alongitudinal direction beyond said first end portion of said secondlayer over said substantial portion of the width of the base layer toform a projecting end of said base layer, (d) said second layer having asecond end portion extending longitudinally beyond said second end edgeof said base layer over at least a substantial portion of the width ofsaid base layer, said second end portion so extending from a positionadjacent said top edge of said base layer to a position at or near saidbottom edge of said base layer to form a projecting end of said secondlayer, (e) so that when two or more of said shingles are assembled endto end to form a horizontal course of shingles, said projecting end ofsaid second layer of one shingle will extend over the projecting end ofsaid base layer of an adjacent shingle to form a shiplap joint, wherebyto protect the joint between adjacent shingles from penetration by rain.

[0006] Further objects and advantages of the invention will appear fromthe following description, taken together with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In the drawings:

[0008]FIG. 1a is a top view of a double laminate shingle according tothe invention;

[0009]FIG. 1b is an isometric view of the double laminate shingle ofFIG. 1;

[0010]FIG. 2 is a top view showing several courses of prior art shingleson a roof, laid so as to illustrate the joint coverage problem;

[0011]FIG. 3a is a top view of a modified double laminate shingleaccording to the invention;

[0012]FIG. 3b is an isometric view of the double laminate shingle ofFIG. 3a;

[0013]FIG. 4a is a top view of a triple laminate shingle according tothe invention;

[0014]FIG. 4b is an isometric view of the triple laminate shingle ofFIG. 4a;

[0015]FIG. 5a is a top view of another triple laminate shingle accordingto the invention;

[0016]FIG. 5b is an isometric view of the triple laminate shingle ofFIG. 4a.

[0017]FIG. 6a is a top view of still another triple laminate shingleaccording to the invention;

[0018]FIG. 6b is an isometric view of the shingle of FIG. 6a; and

[0019]FIG. 6c is a top view of a strip used in the FIG. 6a shingle.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

[0020] In conventional multi-layer asphalt roofing shingles, the typicalsize of each shingle is about 39⅜″ (long)×13¼″ (wide). Usually, suchshingles are installed across the roof in horizontal courses, withoutoverlapping any other shingles in the same horizontal course. Howeverthey overlap the shingles in the preceding course, as courses or rowsare applied vertically up the roof. In addition, each course of shinglesis installed with an offset horizontally to the preceding course, sothat joints between the shingles in the same course do not line up withthe joints between the shingles in the preceding course or succeedingcourse. In the aforementioned shingle, the typical exposure of theshingle is about 5⅝″ out of the 13¼″ width of the shingle. In the otherwords, 7⅝″ (from the total shingle width of 13¼″) is the headlapportion, which is covered by the shingles in the succeeding course afterinstallation. (More generally, the exposure portion is usually the widthof the shingle less 2″, divided by 2, which yields the 5⅝″ exposureportion in the above example.)

[0021] In the example given, the headlap-to-exposure ratio of theshingle is 7⅝″ divided by 5⅝″ and is equal to 1.36. To avoid rain waterleaking through the joints between two consecutive shingles in the samehorizontal course, it is clearly important not to reduce theheadlap-to-exposure ratio close to one or less than one. All portions ofthe vertical joint between horizontally adjacent shingles in the samecourse must either be placed on top of the shingles in the precedingcourse or be covered by the shingles in the succeeding course.

[0022] The inventor has realized that when multiple layer laminateshingles are used, they can be designed to provide a shiplap featurewhich can eliminate the restriction that the headlap-to-exposure ratiomust be greater than 1. Once the restriction is removed, theheadlap-to-exposure ratio can be reduced significantly. A smallershingle width will then be required to provide the same amount of roofcoverage area, or alternatively the same overall shingle width canprovide a larger amount of roof coverage area.

[0023] A shiplap joint is the overlapping portion of two consecutiveshingles in the same course after installation. Reference is first madeto FIGS. 1a, 1 b which show a double laminate shingle 10. Shingle 10includes a base layer 12 having longitudinally spaced-apart end edges14, 16 which define between them the length of the shingle base layer,and laterally spaced-apart top and bottom edges 18, 20 which definebetween them the width of the base layer. (When the shingle 10 is laid,the top edge 18 will be at the top of the headlap portion and the bottomedge 20 will be at the bottom of the exposure portion.)

[0024] Shingle 10 also includes a second layer 24, formed in the FIGS.1a, 1 b embodiment by four individual tabs 26, 28, 30, and 32. Thenumber, spacing and size of these tabs is largely optional, except aswill be explained. (For example, the tabs 26, 28, 30 and 32 can be ofsubstantially equal size.) The tabs 26-32, which can have various colorsof granules applied to them, are laminated to the base layer 12 inconventional fashion, with slots 34 between the tabs 26-32 to provide anornamental appearance.

[0025] In accordance with the invention, one end tab 26 has an end edge36 extending longitudinally beyond the end edge 14 of the base layer 12by a first longitudinal offset indicated at 38. Typically the firstlongitudinal offset 38 is about 2″ to 6″.

[0026] Similarly, the end edge 40 of the fourth tab 32 is inset from theend edge 16 of the base layer by a second longitudinal offset 42 whichis preferably of the same longitudinal extent as offset 38 (althoughoffset 42 can be slightly smaller or larger if desired).

[0027] It will be realized that the end edges 36, 40 will usually not bestraight, since they are cut to a shape such that the end edge 36 of oneshingle, and the end edge 40 of its adjacent shingle, form one of theslots 34 when the shingles are installed on a roof.

[0028] Thus, the shingle 10 has at one end a projecting tab portion 44and at the other end a projecting base layer portion 46. When theshingles 10 are installed in a horizontal course across the roof, theprojecting tab portion 44 will cover the projecting base layer portion46 for adjacent shingles, thus forming a set of shiplap joints whichcover any gaps between horizontally adjacent shingles in the samecourse. Therefore, no rain water can leak through the joints, even ifthe joints are neither placed on top of shingles in the preceding(lower) course nor covered by the shingles in the succeeding (nexthigher) course. Therefore, the headlap-to-exposure ratio no longer needsto be greater than 1. However, preferably the headlap width 48 of thedouble laminate shingle 10 is larger than 2″, to provide sufficientoverlapping area between successive courses of shingles to avoid rainwater being driven up between the courses by high winds and leakingthrough in the headlap area. The exposure portion of the shingle may bebetween 6″ and 18″. The headlap-to-exposure ratio can be reduced frommore than 1 to 1.0 or less, or (preferably) 0.5 or less.

[0029] In the FIGS. 1a, 1 b embodiment, it will be seen that the tab 26which has the projecting portion 44 extends fully from the top edge 18to the bottom edge 20 of the base layer 12. With this arrangement, thevertical joint between horizontally adjacent shingles is fully covered(from top to bottom) by the projecting tab portion 44. However it is notessential that the projecting tab portion 44 extend over the full widthof the shingle, although it is desirable that it do so, or at least thatit extend over most of the shingle width. It is particularly desirablethat the tab 26 extend to a position adjacent (at or near) the top edge18 of the base layer 12. The bottom edge of the tab 26 can be displacedslightly upwardly from the bottom edge 20 of the base layer 12 (e.g. fordecorative purposes), but it should preferably be close to (e.g. withinan inch or two of the bottom edge 20 of the base layer 12.

[0030] The reasons for this will best be understood from FIG. 2, whichshows portions of three courses of prior art shingles 50 laid on a roof(without any shiplap joints). For purposes of illustration, the priorart shingles 50 may each be assumed to be three units wide (i.e. high)and have vertical joints 52 between horizontally adjacent shingles. Inthis arrangement, and looking at joint 52-1, it will be seen that thetop ⅓ of this joint (indicated at 52-1 a and located in the headlapportion 54) will be covered by the succeeding course, and in additionthe bottom third of the joint (indicated at 52-1 c) will be protected bythe preceding course which is beneath it. However the middle third ofthe joint (indicated at 52-1 b) is exposed and will be penetrated byrain. It is this middle portion 52-1 b of the joint which needs to beprotected by the shiplap joint. In theory the shiplap joint can extendonly a short distance above and below the middle third 52-1 b of thejoint 52-1 and will provide protection against rain penetration. Howeverin practice this would not normally be sufficient to prevent wind drivenrain penetration. Therefore it is preferred that the tab 26 having theprojecting portion 44 extend from a position at or close to the top edge18, to a position at or close to, or at least not spaced too much above,the bottom edge 20 of the base layer 12.

[0031] Reference is next made to FIGS. 3a, 3 b which show a doublelaminate shingle very similar to that of FIGS. 1a, 1 b, and in whichprimed reference numerals indicate corresponding parts. The onlydifference between the FIGS. 3a, 3 b embodiment and that of FIGS. 1a, 1b is that in the FIGS. 3a, 3 b embodiment, the second layer 24′ isformed from a single sheet instead of from a plurality of individualtabs. The second layer 24′ contains cutouts or slots 34′ extending fromits bottom edge over part of its width to form decorative tabs, whichcan have various colors of granules applied thereto.

[0032] Reference is next made to FIGS. 4a, 4 b, which show an embodimentwhich is the same as that of FIGS. 3a, 3 b except that a longitudinallyextending narrow strip 60 (which forms a third layer) has been adheredon top of the headlap portion of the double laminate shingle, adjacentthe top edge 18′. The length of the narrow strip 60 can be equal to orless than the overall length of the second layer 24′. The strip 60 doesnot affect the shiplap joint previously described, but when the shinglesof FIGS. 4a, 4 b are installed on a roof, the butts of the shingles ineach succeeding course will line up with the bottom longitudinal edgesof the narrow strips 60. Therefore these shingles after installationwill to some extent have the appearance of more costly triple laminateshingles.

[0033]FIGS. 5a, 5 b show another design which is the same as that ofFIGS. 4a, 4 b except that strip 60 has been omitted and a narrow strip62 has now been adhered beneath the base layer 12′, flush with the buttor bottom edge 20′ of the base layer 12′. Again the length of the narrowstrip 62 can be equal to or less than the length of the base layer 12′and will provide the appearance of a more costly triple laminateshingle.

[0034] Finally, reference is made to FIGS. 6a, 6 b and 6 c, which showan embodiment similar to that of FIGS. 5a, 5 b except that the narrowstrip or third layer 64 (similar to strip 62) is now irregular in shape,having wider portions 66, which project below the bottom edge 20′ of thebase layer 12′ in selected locations as shown for projections 68. Theprojections 68 can be of desired width, e.g. ¼ to {fraction (1/2)} inch,or they can be of different widths, or they can be slanted, i.e.starting at zero projection and ending at ¼ or {fraction (1/2)} inch.The projections 68 will normally have colored granules applied thereto(as will the remainder of the exposed portions of the shingles), but useof granules in the remainder of strip 64 is optional. Preferably thelocations for projections 68 are chosen to be aligned with tabs of thesecond layer, e.g. the second and fourth tabs 28′, 32′, as shown inFIGS. 6a, 6 b. This again provides a more decorative appearance for theshingle, at relatively low cost.

[0035] While preferred embodiments of the invention have been described,it will be understood that modifications may be made within the scope ofthe invention, and such scope is intended to be limited only by theattached claims.

1. A roofing shingle comprising: a) a base layer having first and secondlongitudinally spaced-apart end edges defining between them a length forsaid base layer, said base layer also having laterally spaced-apart topand bottom edges defining a width for said base layer, said base layerhaving an upper surface, b) a second layer laminated to said uppersurface of said base layer, c) said second layer having a first endportion inset from said first end edge of said base layer over at leasta substantial portion of the width of said base layer, said first endportion being inset from said first end edge from a position adjacentsaid top edge of said base layer to a position at or near said bottomedge of said base layer, so that said first end edge of said base layerextends in a longitudinal direction beyond said first end portion ofsaid second layer over said substantial portion of the width of the baselayer to form a projecting end of said base layer, d) said second layerhaving a second end portion extending longitudinally beyond said secondend edge of said base layer over at least a substantial portion of thewidth of said base layer, said second end portion so extending from aposition adjacent said top edge of said base layer to a position at ornear said bottom edge of said base layer to form a projecting end ofsaid second layer, e) so that when two or more of said shingles areassembled end to end to form a horizontal course of shingles, saidprojecting end of said second layer of one shingle will extend over theprojecting end of said base layer of an adjacent shingle to form ashiplap joint, whereby to protect the joint between adjacent shinglesfrom penetration by rain.
 2. A roofing shingle according to claim 1 andhaving a headlap area adapted to be covered by the next higher course ofshingles, and an exposed area adapted to be visible on a roof, andwherein the ratio of said headlap area to said exposed area is less thanor equal to
 1. 3. A roofing shingle according to claim 2 wherein saidratio is less than
 1. 4. A roofing shingle according to claim 3 whereinsaid ratio is less than 0.5.
 5. A roofing shingle according to claim 3wherein the length of said projecting end of said base layer and thelength of said projecting end of said second layer are substantially thesame.
 6. A roofing shingle according to claim 5 wherein said length ofsaid projecting portions is between 2 inches and 6 inches.
 7. A roofingshingle according to claim 1 wherein said second layer comprises aplurality of separate portions.
 8. A roofing shingle according to claim1 wherein said second layer comprises a single sheet having cutoutstherein to form tabs.
 9. A roofing shingle according to claim 1 andincluding a third sheet laminated on top of a portion of said secondlayer.
 10. A roofing shingle according to claim 1 and including a thirdsheet laminated beneath said base layer.
 11. A plurality of roofingshingles each in accordance with claim 1, said roofing shingles beingassembled end-to-end to form a horizontal course of shingles withvertical joints between them, at least a substantial portion of saidvertical joint between each adjacent pair of shingles being covered by asaid projecting end of said second layer of one of said shingles.